Passive preamps, whether transformer or resistor based, work just fine with all the Dynaco tube amps that I have tried them with. Most CD players are set up for about 2 to 2.1 volt output. Most Dynaco amps only need a little more than 1 volt for full output. Most upgrade driver boards for Dynaco amps will allow the amp to achieve full output with even less input voltage.

The biggest advantage to a passive is that it nearly always will add less of any "sonic signature" to the music than a powered preamp.

Bob

Last edited by Bob Latino on Tue Jul 06, 2010 5:23 pm; edited 1 time in total

I can say nothing bad about the performance of going passive with a Dynaco Stereo 70 or other typical tube amplifier. Note that the volume potentiometer (multiple is the best way since not all recordings are ideally balanced left/right) should be of top quality.

With solid state equipment, the low input impedance "seen" by the source could be a problem. Not all tubed phono stages and output stages on tubed CD players like low input impedances; you'd be setting yourself up for a bass rolloff if the equipment is thus mismatched.